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Search: id:A118071
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| A118071 |
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Primes which are sum of twin prime pair + 1. |
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+0
3
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| 13, 37, 61, 277, 397, 457, 541, 1201, 1237, 1321, 1621, 1657, 2557, 2857, 3217, 4057, 4177, 4261, 4621, 5101, 5581, 6337, 6661, 6781, 7057, 7537, 8101, 8317, 8461, 8521, 8677, 9277, 9601, 10837, 10957, 11317, 11701, 12541, 12601, 12721, 13381, 13921
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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Subset of A092738 - Paolo P. Lava (ppl(AT)spl.at), Dec 21 2007
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FORMULA
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{A001359(k) + A006512(k) + 1} INTERSECT {A000040}. {A054735(k) + 1} INTERSECT {A000040}. {2*A001359(k) + 3} INTERSECT {A000040}.
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EXAMPLE
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a(1) = 13 = 5 + 7 + 1 where (5,7) is a twin prime pair.
a(2) = 37 = 17 + 19 + 1.
a(3) = 61 = 29 + 31 + 1.
a(4) = 277 = 137 + 139 + 1.
a(5) = 397 = 197 + 199 + 1.
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MAPLE
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P:=proc(n) local a, i; for i from 1 by 1 to n do if ithprime(i+1)-ithprime(i)=2 then a:=ithprime(i+1)+ithprime(i)+1; if isprime(a) then print(a); fi; fi; od; end: P(300); - Paolo P. Lava (ppl(AT)spl.at), Dec 21 2007
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MATHEMATICA
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lst={}; d=2; Do[p1=Prime[n]; p2=Prime[n+1]; p=p1+p2+1; If[PrimeQ[p]&&p2-p1==d, AppendTo[lst, p]], {n, 10^3}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Aug 14 2008]
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CROSSREFS
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Cf. A000040, A001359, A006512, A054735.
Sequence in context: A034938 A139530 A138368 this_sequence A147207 A146877 A049742
Adjacent sequences: A118068 A118069 A118070 this_sequence A118072 A118073 A118074
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KEYWORD
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easy,nonn
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AUTHOR
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Jonathan Vos Post (jvospost3(AT)gmail.com), May 11 2006
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EXTENSIONS
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Added more terms Vladimir Orlovsky (4vladimir(AT)gmail.com), Mar 10 2009
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